1. Technical Field
The present invention relates to a thermal detector, a thermal detection device, and an electronic instrument.
2. Related Art
Pyroelectric-type and bolometer-type infrared detection devices are known to be thermal detection devices. With infrared detection devices, infrared light is detected as the result of using the change in spontaneous polarization amount of a pyroelectric body material (pyroelectric effect or pyroelectron effect) occurring in accordance with the amount of infrared light that has been absorbed (temperature) in order to produce excitation force (charge due to polarization) across the two terminals of the pyroelectric body (pyroelectric-type) or in order to bring about a change in resistance value in accordance with temperature (bolometer-type). The process for producing pyroelectric infrared detection devices is complicated in comparison to bolometer-type infrared detection devices, but they have the advantage of superior detection sensitivity.
Cells of pyroelectric infrared detection devices have infrared detecting elements that contain capacitors that are formed from a pyroelectric body that is connected to an upper electrode and a lower electrode. Various types of electrode and pyroelectric body materials, as well as electrode wiring structures, have been offered (see, Japanese Laid-Open Patent Application Publication No. 10-104062).
In addition, because the thermal detection element is mounted on a membrane (support member), and a cavity part is formed between the membrane and the substrate on which the thermal detection element is formed, the thermal detection element is thermally isolated from the substrate.
In addition, studies are being conducted regarding configurations in which a detection circuit disposed on the substrate and the detection circuit is connected to the infrared detector using wiring that is disposed on the membrane.